Picometer
A picometer (pm) is an extremely small unit of length in the metric system, equal to one-trillionth of a meter (1 pm = 10⁻¹² meters). Picometers are used to measure things on the atomic and subatomic scale, such as the size of atoms or the distance between particles in a molecule. For example, a hydrogen atom is about 50 picometers in radius. This unit is mainly used in physics, chemistry, and nanotechnology. Because it's so small, you won’t see picometers used in everyday life — they are only relevant in scientific research where ultra-precise measurements are required.
Cubit (Greek)
The Greek cubit is an ancient unit of length based on the forearm’s length—from the elbow to the tip of the middle finger. In ancient Greece, it typically measured about 18 to 20 inches (approximately 45 to 50 centimeters), though the exact length could vary by region and period.
The Greek cubit was widely used in architecture, construction, and land measurement. It played a crucial role in building temples, monuments, and other structures in classical Greece.
Key points:
Greek cubit ≈ 18 to 20 inches (45–50 cm)
Based on the length of the forearm
Used in ancient Greek construction and land surveying
Important for classical architecture and engineering
This unit reflects how ancient civilizations used the human body as a natural measuring tool before standardized systems.
No conversions available for length.